National Physical Laboratory

Supply of thermal test objects

Tissue mimicking materials Thermal Test Object 1Early Thermal Test Object
with transparent entry
membrane showing
central white disk of
tissue mimicking material
and thermocouple

Several ultrasound-related products are available, either directly from NPL or from our ultrasound partner organisation, Precision Acoustics Ltd.

We can supply two different thermal test objects.

The first of these utilises the agar-based TMM and is intended for testing compliance with the limits for transducer surface temperature specified in IEC 60601-2-37. It is supplied with silicone rubber skin-mimicking layers for use when necessary.

The second type is for more general testing and research into ultrasound heating. It consists of a thin-film thermocouple sandwiched between pieces of the gelatine-based TMM. This Thermal Test Object is mounted in a 3-axis positioning system. The transducer is held above the TTO and acoustical attenuators (white discs) are placed between the two. This is mounted in a closed container with an acoustically transparent window. The design and performance is described in IEC62306.


Customer Service tel: +44 20 8943 8631

Last Updated: 29 Nov 2018
Created: 7 Apr 2010


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